Awesome Moments: Derek and Betty taking down the full-sized gargan with the former climbing a power line to wire it to the disintegrator ray and the latter getting the assistance of the power plant to first cut the power so Derek didn't electrocute himself, then provide enough juice to power the ray gun.
Complete Monster: Thor is one of the aliens sent to manage the gargons, and the most enthusiastic supporter of his species being the "superior race". The very first thing we see him do is disintegrate a puppy. After Derek protests that a civilized society exists on the planet, Thor suggests he be Forced to Watch as all life on Earth is destroyed. After Derek escapes, Thor is sent off to capture him. In his pursuit, he kills almost anybody who annoys him or is of no use to him. After he is captured by Derek, he urges him to kill any humans around.
Nightmare Fuel: While it avoids Bloodier and Gorier due to its limited budget and the time it was made, the on screen disintegrations still manage to be quite unsettling even with the Special Effects Failure. Especially because of how trigger-happy Thor is, and the rather high body count that results.
The live lobster near the beginning probably blew the budget. Later gargons are played by what looks like a black-painted vaguely lobster-shaped cardboard cutout. (They probably intended to do some process work to replace the silhouette with an actual lobster image, but didn't have the budget.)
All of the human skeletons are played by a single-bolted-joint specimen straight from a school science lab (which means that Alice's body accidentally has male hips). In the shot where Prof. Simpson's body is discovered, the aperture is clearly visible.
On the other hand, when you consider the next-to-nothing budget the film had, you have to be impressed that the movie's non-special effects work. For example, the entire movie was shot wild track: every single sound was dubbed in later — and unlike certain other B-movies, you can't really tell.
The mass spaceship crash at the end is clearly stock footage of an erupting volcano.
Averted with the two scenes of the spaceship landing. All things considered, it's actually a pretty nice special effect.
Tear Jerker: Derek's line of, "You... knew your brother?" to Betty. It's the one line in the film where Derek realizes that Earth contains a familial society he had only read of in books and grows to love it enough to the point of pulling off a willing Heroic Sacrifice to protect it.
